Standard FITS template for simulated astrophysical scenes with the WFIRST coronagraph

The science investigation teams (SITs) for the WFIRST coronagraphic instrument have begun studying the capabilities of the instrument to directly image reflected light off from exoplanets at contrasts down to contrasts of ~10^-9 with respect to the stellar flux. Detection of point sources at these high contrasts requires yield estimates and detailed modeling of the image of the planetary system as it propagates through the telescope optics. While the SITs might generate custom astrophysical scenes, the integrated model, propagated through the internal speckle field, is typically done at JPL. In this white paper, we present a standard file format to ensure a single distribution system between those who produce the raw astrophysical scenes, and JPL modelers who incorporate those scenes into their optical modeling. At its core, our custom file format uses FITS files, and incorporates standards on packaging astrophysical scenes. This includes spectral and astrometric information for planetary and stellar point sources, zodiacal light and extragalactic sources that may appear as contaminants. Adhering to such a uniform data distribution format is necessary, as it ensures seamless work flow between the SITs and modelers at JPL for the goals of understanding limits of the WFIRST coronagraphic instrument.Comment: 8 pages, white pape

Control interface concepts for CHARA 6-telescope fringe tracking with CHAMP+MIRC

Cophasing six telescopes from the CHARA array, the CHARA-Michigan Phasetracker (CHAMP) and Michigan Infrared Combiner (MIRC) are pushing the frontiers of infrared long-baseline interferometric imaging in key scientific areas such as star- and planet-formation. Here we review our concepts and recent improvements on the CHAMP and MIRC control interfaces, which establish the communication to the real-time data recording & fringe tracking code, provide essential performance diagnostics, and assist the observer in the alignment and flux optimization procedure. For fringe detection and tracking with MIRC, we have developed a novel matrix approach, which provides predictions for the fringe positions based on cross-fringe information.Comment: 6 pages, 4 figures, published in SPIE conference proceedings (http://dx.doi.org/10.1117/12.926559

Phase Closure Nulling: results from the 2009 campaign

We present here a new observational technique, Phase Closure Nulling (PCN), which has the potential to obtain very high contrast detection and spectroscopy of faint companions to bright stars. PCN consists in measuring closure phases of fully resolved objects with a baseline triplet where one of the baselines crosses a null of the object visibility function. For scenes dominated by the presence of a stellar disk, the correlated flux of the star around nulls is essentially canceled out, and in these regions the signature of fainter, unresolved, scene object(s) dominates the imaginary part of the visibility in particular the closure phase. We present here the basics of the PCN method, the initial proof-of-concept observation, the envisioned science cases and report about the first observing campaign made on VLTI/AMBER and CHARA/MIRC using this technique.Comment: To be published in the proceedings of the SPIE'2010 conference on "Optical and Infrared Interferometry II

A molecular basis for selective antagonist destabilization of dopamine D3 receptor quaternary organization

The dopamine D3 receptor (D3R) is a molecular target for both first-generation and several recently-developed antipsychotic agents. Following stable expression of this mEGFP-tagged receptor, Spatial Intensity Distribution Analysis indicated that a substantial proportion of the receptor was present within dimeric/oligomeric complexes and that increased expression levels of the receptor favored a greater dimer to monomer ratio. Addition of the antipsychotics, spiperone or haloperidol, resulted in re-organization of D3R quaternary structure to promote monomerization. This action was dependent on ligand concentration and reversed upon drug washout. By contrast, a number of other antagonists with high affinity at the D3R, did not alter the dimer/monomer ratio. Molecular dynamics simulations following docking of each of the ligands into a model of the D3R derived from the available atomic level structure, and comparisons to the receptor in the absence of ligand, were undertaken. They showed that, in contrast to the other antagonists, spiperone and haloperidol respectively increased the atomic distance between reference α carbon atoms of transmembrane domains IV and V and I and II, both of which provide key interfaces for D3R dimerization. These results offer a molecular explanation for the distinctive ability of spiperone and haloperidol to disrupt D3R dimerization

DISTANCE AND FACE-TO-FACE LEARNING CULTURE AND VALUES: A CONCEPTUAL ANALYSIS

With distance learning increasing in popularity across the country and the world, a review of the extant literature as it relates to distance learning and face-to-face learning is warranted. In particular, this paper examined distance learning, including a historical overview, prevailing themes in past research, and studies relating the importance of the community concept in distance education. Also analyzed were research studies in which the importance of culture and values were addressed. Subsequently, the rationale for the development of instruments to quantify values, including the Schwartz Value Scale (SVS), was provided. Growth in online education has created an environment where educators must meet new challenges while having little practical experience. Research, then, is – and will be – needed to guide future practice and pedagogy. Therefore, to provide institutions with much-needed information about the value profile of the distance-learning student, it is essential that research on student values is performed. This information could aid in the creation and implementation of programs aimed at increasing student success and decreasing student withdrawals. In sociological terms, then, distance-learning courses would meet the criteria set forth for societies: courses are groupings of individuals living or participating in a territorial space. Furthermore, courses contain formal, and develop informal, structures that regulate the allocation of rewards

Fibre Length Distribution and Dispersion during the Injection Moulding Process: An experimental study evaluating fibre length attrition and dispersion during processing of long glass fibre reinforced polymer composites in injection moulding including an evaluation of long glass fibre measurement techniques

This project evaluates fibre length dispersion and distribution within the injection moulding process of long glass fibre reinforced polypropylene, sponsored by Autodesk Simulation. The primary material used in this investigation was a 15 mm long glass fibre reinforced polypropylene consisting of two fibre content levels, 20 wt. % and 40 wt. %. A review of previous research was compiled in this study to evaluate various glass fibre measurement methods and fibre breakage studies to establish where along the injection moulding process fibre breakage predominantly occurs and which process parameters have the greatest influence on fibre length distribution along the screw. Based on literature findings, a manual fibre length measurement method was developed and applied in this study and benchmarked against existing commercially available automated software programs and found to be more accurate in obtaining a reliable fibre length distribution within a glass fibre reinforced sample. Fibre length measurements from the nozzle confirmed that the majority of fibre breakage had already occurred in the screw. Measurements taken along the screw showed a drastic decrease in weighted average glass fibre length from initial pellet form to the end of the metering zone with sudden transitions to lower weighted average values seen at the beginning of the feeding zone and along the compression zone. Fibre dispersion results from the nozzle and along the screw through the use of a μ-CT scanner showed a complex fibre flow and orientation of fibres with the preservation of fibre clusters being seen all along the injection moulding process but chiefly in the feeding and compression zones of the screw

Diseño y Validación de un instrumento para la evaluación y priorización en los componentes Técnicos y financieros de los predios propuestos por los municipios, para participar en proyectos Bancos Municipales de Agua (BAMA) en la Jurisdicción de la Corporación Autónoma Regional de Cundinamarca CAR

Los Bancos municipales de agua (BAMA), hacen parte de las estrategias adelantadas por parte de la Corporación Autónoma de Cundinamarca (CAR), para mitigar los impactos ambientales generados por el cambio climático, la cual busca dotar a los municipios de estructuras de almacenamiento de agua de escorrentía superficial en un cauce definido durante las épocas de lluvias. Esto permite regular las fuentes de captación en épocas de lluvias y en épocas de sequía disponer de un volumen de agua para atender las necesidades propias de la región para actividades relacionadas con la agricultura, atención de incendios y suministro de agua para usos diferentes al consumo humano. La CAR invitó a los 104 municipios de su jurisdicción a participar en la postulación de predios para la construcción de este tipo de proyectos; sin embargo y debido a que la mayoría de los predios no cumplen con los requerimientos técnicos mínimos, existe la necesidad de establecer un procedimiento de evaluación que permita depurar los predios propuestos y priorizar aquellos que cumplen con los requerimientos mínimos que permitan la ejecución de un proyecto tipo BAMA. Para realizar dicha evaluación se propuso el análisis de los componentes Técnico, Ambiental, Social y Financiero, siendo como objeto de este proyecto de grado llevar a cabo la evaluación de los componentes Técnico y Financiero, los cuales se complementan con los Ambientales y Sociales, abordados en otro trabajo de grado (Ing. Barbara Rico). Una vez definido el procedimiento de evaluación de cada uno de los componentes se elaboró una herramienta que consolida la información y emite una puntuación, la cual fue validada con información de proyectos ya ejecutados buscando generar una escala de referencia y así su priorización con respecto a los componentes propuestos.#DiseñoValidaciónInstrumentoEvaluaciónComponentesTécnicosFinancierosPrediosPropuestosMunicipiosProyectos(BAMA)JurisdicciónCAR#ValidaciónInstrumentoEvaluaciónComponentesTécnicosFinancierosPrediosPropuestosMunicipiosProyectos(BAMA)#DiseñoValidaciónInstrumentoEvaluaciónTécnicosFinancierosPrediosPropuestosMunicipiosProyectos(BAMA)CARCundinamarcaThe municipal water banks (BAMA), are part of the strategies advanced by part of the Autonomous Corporation of Cundinamarca (CAR), to mitigate the impacts environmental issues generated by climate change, which seeks to provide municipalities with surface runoff water storage structures in a defined channel during the rainy seasons. This allows the catchment sources to be regulated in periods of rains and in times of drought have a volume of water to meet the needs of the region for activities related to agriculture, attention to fires and water supply for uses other than human consumption. The CAR invited the 104 municipalities of its jurisdiction to participate in the application of properties for the construction of this type of projects; however, and because most of the properties do not meet the minimum technical requirements, there is a need to establish an evaluation procedure that allows purging the proposed properties and prioritize those that meet the minimum requirements that allow the execution of a BAMA-type project. To carry out this evaluation, the analysis of the Technical, Environmental, Social and Financial components, being the object of this degree project to carry out the evaluation of the Technical and Financial components, which are complemented by the Environmental and Social ones, addressed in another work degree (Ing. Barbara Rico). Once the evaluation procedure for each One of the components developed a tool that consolidates the information and issues a score, which was validated with information from projects already executed seeking to generate a reference scale and thus its prioritization with respect to the proposed component

The Circumstellar Environments of Young Stars at AU Scales

We review recent advances in our understanding of the innermost regions of the circumstellar environment around young stars, made possible by the technique of long baseline interferometry at infrared wavelengths. Near-infrared observations directly probe the location of the hottest dust. The characteristic sizes found are much larger than previously thought, and strongly correlate with the luminosity of the central young stars. This relation has motivated in part a new class of models of the inner disk structure. The first mid-infrared observations have probed disk emission over a larger range of scales, and spectrally resolved interferometry has for the first time revealed mineralogy gradients in the disk. These new measurements provide crucial information on the structure and physical properties of young circumstellar disks, as initial conditions for planet formation.Comment: to appear in Protostars and Planets V boo

Recent developments in optical interferometry data standards

A working group on interferometry data standards has been established within IAU Commission 54 (Optical/ Infrared Interferometry). The working group includes members representing the major optical interferometry projects worldwide, and aims to enhance existing standards and develop new ones to satisfy the broad interests of the optical interferometry community. We present the initial work of the group to enhance the OIFITS data exchange standard, and outline the software packages and libraries now available which implement the standard

Confronting Standard Models of Proto--Planetary Disks With New Mid--Infrared Sizes from the Keck Interferometer

We present near and mid-infrared interferometric observations made with the Keck Interferometer Nuller and near-contemporaneous spectro-photometry from the IRTF of 11 well known young stellar objects, several observed for the first time in these spectral and spatial resolution regimes. With AU-level spatial resolution, we first establish characteristic sizes of the infrared emission using a simple geometrical model consisting of a hot inner rim and mid-infrared disk emission. We find a high degree of correlation between the stellar luminosity and the mid-infrared disk sizes after using near-infrared data to remove the contribution from the inner rim. We then use a semi-analytical physical model to also find that the very widely used "star + inner dust rim + flared disk" class of models strongly fails to reproduce the SED and spatially-resolved mid-infrared data simultaneously; specifically a more compact source of mid-infrared emission is required than results from the standard flared disk model. We explore the viability of a modification to the model whereby a second dust rim containing smaller dust grains is added, and find that the two-rim model leads to significantly improved fits in most cases. This complexity is largely missed when carrying out SED modelling alone, although detailed silicate feature fitting by McClure et al. 2013 recently came to a similar conclusion. As has been suggested recently by Menu et al. 2015, the difficulty in predicting mid-infrared sizes from the SED alone might hint at "transition disk"-like gaps in the inner AU; however, the relatively high correlation found in our mid-infrared disk size vs. stellar luminosity relation favors layered disk morphologies and points to missing disk model ingredients instead